The first blast took place at a commercial area on Jolo island. This blast claimed the lives of six people, and injured about 30, the police said.
The second blast took place two hours later next to a parked military patrol jeep in Iligan city. This injured at least 10 people, including three soldiers, the military said.
Since the first bomb was hidden beneath the saddle of a motorcycle, the military officials suspect the involvement of al-Qaeda.
"This is a signature bomb attack of the Abu Sayyaf," Major General Juancho Sabban was quoted as saying in a news agency report.
Abu Sayyaf is a well known and a wanted terrorist who is believed to have been behind many bombings and kidnaps. In Jan 2009, he allegedly kidnapped three Red Cross workers, and the militants are still holding one of them who is an Italian.